AREA_ATTRIBUTE

The AREA ATTRIBUTE table records facts about areas.

Field	Required	Type	Description
area_attribute_id	Yes	integer	A system-generated unique identifier for each exposure event.
area_id	Yes	integer	A foreign key to the Person who is subjected to the exposure.
attribute_concept_id	Yes	integer	A foreign key to the standard concept identifier in the Standardized Vocabularies.
attribute_start_date	Yes	date	The date the exposure started.
attribute_end_date	No	date	The date the exposure ended.
value_as_number	No	float	The exposure value stored as a number.
value_as_concept_id	No	integer	A foreign key to a exposure value represented as a Concept from the Standardized Vocabularies.
value_source_value	No	varchar(50)	The source value associated with the content of the value_as_number or value_as_concept_id as stored in the source data.
unit_concept_id	No	integer	A foreign key to a Standard Concept ID of Measurement Units in the Standardized Vocabularies.
unit_source_value	No	varchar(50)	The source code for the unit as it appears in the source data
qualifier_concept_id	No	integer	A foreign key to a Standard Concept ID of the qualifier in the Standardized Vocabularies.
qualifier_source_value	No	varchar(50)	The source code for the qualifier as it appears in the source data
attribute_source_concept_id	No	integer	A foreign key to a Concept in the Standard Vocabularies that refers to the code used in the source.
attribute_source_value	No	varchar(50)	The Exposure name as it appears in the source data.
data_source_id	No	integer	A foreign key to the data_source which the exposure is derived from.